findChild

Find a child node by name.
This may be overridden in subclasses to provide a more advanced way of finding the
child, but the default implementation simply scans through the list of nodes
to find the first one with the requested name.

Normally the list of nodes should have been computed by the time this returns,
but see Children.getNodes() for an important caveat as to why this may not
be doing what you want and what to do instead.

createNodes

Create nodes representing copies of the original node's children.
The default implementation returns exactly one representative for each original node,
as returned by copyNode(org.openide.nodes.Node).
Subclasses may override this to avoid displaying a copy of an original child at all,
or even to display multiple nodes representing the original.

add

Add nodes to this container but do not call this method.
If you think you need to do this probably you really wanted to use
Children.Keys.setKeys(java.util.Collection<? extends T>) instead.
The parent node of these nodes
is changed to the parent node of this list. Each node can be added
only once. If there is some reason a node cannot be added, for example
if the node expects only a special type of subnodes, the method should
do nothing and return false to signal that the addition has not been successful.

This method should be implemented by subclasses to filter some nodes, etc.